Simplify the following expression: $x = \dfrac{z^2 - 11z + 24}{z - 8} $
Explanation: First factor the polynomial in the numerator. $ z^2 - 11z + 24 = (z - 8)(z - 3) $ So we can rewrite the expression as: $x = \dfrac{(z - 8)(z - 3)}{z - 8} $ We can divide the numerator and denominator by $(z - 8)$ on condition that $z \neq 8$ Therefore $x = z - 3; z \neq 8$